Stephen Sidney

Heart Disease and Stroke Statistics—2006 Update

1. About These Statistics 2. Cardiovascular Diseases 3. Coronary Heart Disease, Acute Coronary Syndrome and Angina Pectoris 4. Stroke and Stroke in Children 5. High Blood Pressure (and End-Stage Renal Disease) 6. Congenital Cardiovascular Defects 7. Heart Failure 8. Other Cardiovascular Diseases 9. Risk Factors 10. Metabolic Syndrome 11. Nutrition 12. Quality of Care 13. Medical Procedures 14. Economic Cost of Cardiovascular Diseases 15. At-a-Glance Summary Tables 16. Glossary and Abbreviation Guide 17. Acknowledgment 18. References Appendix I: List of Statistical Fact Sheets. URL: http://www.americanheart.org/presenter.jhtml?identifier=2007 The American Heart Association works with the Centers for Disease Control and Prevention’s National Center for Health Statistics (CDC/NCHS), the National Heart, Lung, and Blood Institute (NHLBI), the National Institute of Neurological Disorders and Stroke (NINDS), and other government agencies to derive the annual statistics in this update. This section describes the most important sources we use. For more details and an alphabetical list of abbreviations, see the Glossary and Abbreviation Guide. All statistics are for the most recent year available. Prevalence, mortality and hospitalizations are computed for 2003 unless otherwise noted. Mortality as an underlying or contributing cause of death is for 2002. Economic cost estimates are for 2006. Due to late release of data, some disease mortality are not updated to 2003. Mortality for 2003 are underlying preliminary data, obtained from the NCHS publication National Vital Statistics Report: Deaths: Preliminary Data for 2003 (NVSR, 2005;53:15) and from unpublished tabulations furnished by Robert Anderson of NCHS. US and state death rates and prevalence rates are age-adjusted per 100 000 population (unless otherwise specified) using the 2000 …

Racial discrimination and blood pressure : The CARDIA study of young Black and White adults

OBJECTIVES This study examined associations between blood pressure and self reported experiences of racial discrimination and responses to unfair treatment. METHODS Survey data were collected in year 7 (1992/93) of the Coronary Artery Risk Development in Young Adults (CARDIA) study, a prospective multisite community-based investigation. Participants included 831 Black men, 1143 Black women, 1006 White men, and 1106 White women 25 to 37 years old. RESULTS Systolic blood pressure among working-class Black adults reporting that they typically accepted unfair treatment and had experienced racial discrimination in none of seven situations was about 7 mm Hg higher than among those reporting that they challenged unfair treatment and experienced racial discrimination in one or two of the situations. Among professional Black adults, systolic blood pressure was 9 to 10 mm Hg lower among those reporting that they typically challenged unfair treatment and had not experienced racial discrimination. Black-White differences in blood pressure were substantially reduced by taking into account reported experiences of racial discrimination and responses to unfair treatment. CONCLUSIONS Research on racial/ ethnic distributions of blood pressure should take into account how discrimination may harm health.

Population Trends in the Incidence and Outcomes of Acute Myocardial Infarction

BACKGROUND Few studies have characterized recent population trends in the incidence and outcomes of myocardial infarction. METHODS We identified patients 30 years of age or older in a large, diverse, community-based population who were hospitalized for incident myocardial infarction between 1999 and 2008. Age- and sex-adjusted incidence rates were calculated for myocardial infarction overall and separately for ST-segment elevation and non-ST-segment elevation myocardial infarction. Patient characteristics, outpatient medications, and cardiac biomarker levels during hospitalization were identified from health plan databases, and 30-day mortality was ascertained from administrative databases, state death data, and Social Security Administration files. RESULTS We identified 46,086 hospitalizations for myocardial infarctions during 18,691,131 person-years of follow-up from 1999 to 2008. The age- and sex-adjusted incidence of myocardial infarction increased from 274 cases per 100,000 person-years in 1999 to 287 cases per 100,000 person-years in 2000, and it decreased each year thereafter, to 208 cases per 100,000 person-years in 2008, representing a 24% relative decrease over the study period. The age- and sex-adjusted incidence of ST-segment elevation myocardial infarction decreased throughout the study period (from 133 cases per 100,000 person-years in 1999 to 50 cases per 100,000 person-years in 2008, P<0.001 for linear trend). Thirty-day mortality was significantly lower in 2008 than in 1999 (adjusted odds ratio, 0.76; 95% confidence interval, 0.65 to 0.89). CONCLUSIONS Within a large community-based population, the incidence of myocardial infarction decreased significantly after 2000, and the incidence of ST-segment elevation myocardial infarction decreased markedly after 1999. Reductions in short-term case fatality rates for myocardial infarction appear to be driven, in part, by a decrease in the incidence of ST-segment elevation myocardial infarction and a lower rate of death after non-ST-segment elevation myocardial infarction.

Validation and refinement of scores to predict very early stroke risk after transient ischaemic attack

BACKGROUND We aimed to validate two similar existing prognostic scores for early risk of stroke after transient ischaemic attack (TIA) and to derive and validate a unified score optimised for prediction of 2-day stroke risk to inform emergency management. METHODS The California and ABCD scores were validated in four independent groups of patients (n=2893) diagnosed with TIA in emergency departments and clinics in defined populations in the USA and UK. Prognostic value was quantified with c statistics. The two groups used to derive the original scores (n=1916) were used to derive a new unified score based on logistic regression. FINDINGS The two existing scores predicted the risk of stroke similarly in each of the four validation cohorts, for stroke risks at 2 days, 7 days, and 90 days (c statistics 0.60-0.81). In both derivation groups, c statistics were improved for a unified score based on five factors (age >or=60 years [1 point]; blood pressure >or=140/90 mm Hg [1]; clinical features: unilateral weakness [2], speech impairment without weakness [1]; duration >or=60 min [2] or 10-59 min [1]; and diabetes [1]). This score, ABCD(2), validated well (c statistics 0.62-0.83); overall, 1012 (21%) of patients were classified as high risk (score 6-7, 8.1% 2-day risk), 2169 (45%) as moderate risk (score 4-5, 4.1%), and 1628 (34%) as low risk (score 0-3, 1.0%). IMPLICATIONS Existing prognostic scores for stroke risk after TIA validate well on multiple independent cohorts, but the unified ABCD(2) score is likely to be most predictive. Patients at high risk need immediate evaluation to optimise stroke prevention.

Calcium/Vitamin D Supplementation and Cardiovascular Events

Background— Individuals with vascular or valvular calcification are at increased risk for coronary events, but the relationship between calcium consumption and cardiovascular events is uncertain. We evaluated the risk of coronary and cerebrovascular events in the Women’s Health Initiative randomized trial of calcium plus vitamin D supplementation. Methods and Results— We randomized 36 282 postmenopausal women 50 to 79 years of age at 40 clinical sites to calcium carbonate 500 mg with vitamin D 200 IU twice daily or to placebo. Cardiovascular disease was a prespecified secondary efficacy outcome. During 7 years of follow-up, myocardial infarction or coronary heart disease death was confirmed for 499 women assigned to calcium/vitamin D and 475 women assigned to placebo (hazard ratio, 1.04; 95% confidence interval, 0.92 to 1.18). Stroke was confirmed among 362 women assigned to calcium/vitamin D and 377 assigned to placebo (hazard ratio, 0.95; 95% confidence interval, 0.82 to 1.10). In subgroup analyses, women with higher total calcium intake (diet plus supplements) at baseline were not at higher risk for coronary events (P=0.91 for interaction) or stroke (P=0.14 for interaction) if assigned to active calcium/vitamin D. Conclusions— Calcium/vitamin D supplementation neither increased nor decreased coronary or cerebrovascular risk in generally healthy postmenopausal women over a 7-year use period.

Validity and Reliability of Short Physical Activity History: Cardia and the Minnesota Heart Health Program

Validity and reliability of a short physical activity history were assessed in two studies. Validity was studied in 2766 women and 2303 men, participants in CARDIA, a biracial study. Ages ranged from 18 to 30 years. The activities performed in the past 12 months by ≥ 50 percent of participants were walking/hiking, nonstrenuous sports, shoveling/lifting during leisure, running/jogging and home maintenance/gardening. Validity was indirectly assessed by studying the relationships of total activity to skinfold thickness, total caloric intake, duration on a self-limited maximal exercise test, and high density lipoprotein cholesterol. Less than perfect correlation are expected since physical activity is not the only factor affecting the validation criteria and since physical activity patterns change over time within each person. Comparing the highest physical activity quartile to the lowest physical activity quartile, mean level of sum of three skinfolds was 10.7 mm less for women (correlation coefficient (r) = -0.15, P < 0.001) and 6.9 mm less for men (r = -0.12, P < 0.001); mean level of caloric intake was 158 kcal morefor women (r = 0.07, P < 0.001) and 875 kcal morefor men (r = 0.21, P < 0.001); mean level of duration on treadmill was 132 seconds more for women (r = 0.36, P < 0.001) and 95 seconds more for women (r = 0.25, P < 0.001); and mean level of high density lipoprotein cholesterol was 4.8 mg/dL more for women (r = 0.13, P < 0.001) and 3.2 mg/dL more for men (r = 0.11, P < 0.001). Reliability was studied in a separate population by comparing questionnaire results in an initial telephone administration with results obtained two weeks later (N = 129). Similar types and amounts of activity were reported in this group as in the group studied for validity. Test-retest correlation coefficients for three summary scores ranged from 0.77 to 0.84, and were at least 0.57 for each of the 13 activity groupings queried. This questionnaire typically takes 5-10 minutes to administer. It yields moderately detailed information about type and amount of usual leisure time physical activity.

Stroke in Users of Low-Dose Oral Contraceptives

BACKGROUND Previous studies have linked the use of oral contraceptive agents to an increased risk of stroke, but those studies have been limited to oral contraceptives containing more estrogen than is now generally used. METHODS In a population-based, case-control study, we identified fatal and nonfatal strokes in female members of the California Kaiser Permanente Medical Care Program and who were 15 through 44 years of age. Matched controls were randomly selected from female members who had not had strokes. Information about the use of oral contraceptives (essentially limited to low-estrogen preparations) was obtained in interviews. RESULTS A total of 408 confirmed strokes occurred in a total of 1.1 million women during 3.6 million woman-years of observation. The incidence of stroke was thus 11.3 per 100,000 woman-years. On the basis of data from 295 women with stroke who were interviewed and their controls, the odds ratio for ischemic stroke among current users of oral contraceptives, as compared with former users and women who had never used such drugs, was 1.18 (95 percent confidence interval, 0.54 to 2.59) after adjustment for other risk factors for stroke. The adjusted odds ratio for hemorrhagic stroke was 1.14 (95 percent confidence interval, 0.60 to 2.16). With respect to the risk of hemorrhagic stroke, there was a positive interaction between the current use of oral contraceptives and smoking (odds ratio for women with both these factors, 3.64; 95 percent confidence interval, 0.95 to 13.87). CONCLUSIONS Stroke is rare among women of childbearing age. Low-estrogen oral-contraceptive preparations do not appear to increase the risk of stroke.

Risk of Recurrent Childhood Arterial Ischemic Stroke in a Population-Based Cohort: The Importance of Cerebrovascular Imaging

OBJECTIVE. Few data exist regarding rates and predictors of recurrence after childhood arterial ischemic stroke. We sought to establish such rates within a large, multiethnic population and determine whether clinical vascular imaging predicts recurrence. PATIENTS AND METHODS. In a population-based cohort study, we collected data on all documented cases of arterial ischemic stroke among 2.3 million children (<20 years old) enrolled in a northern Californian managed care plan from January 1993 to December 2004. Perinatal strokes were those that occurred by 28 days of life. Data on cerebrovascular imaging (conventional or magnetic resonance angiography), including presence of vascular abnormalities, were abstracted from official radiology reports. We used Kaplan-Meier survival-analysis techniques to determine rates and predictors of recurrent stroke. RESULTS. Among 181 incident childhood stroke cases (84 perinatal; 97 later childhood), there were 16 recurrent strokes (1 after a perinatal stroke) at a median of 2.7 months. The 5-year cumulative recurrence rates were 1.2% after perinatal stroke and 19% after later childhood stroke. Of the 97 children with later childhood strokes, 52 received cerebrovascular imaging, predominantly magnetic resonance angiography (n = 36) and conventional angiography (n = 26). Although there were no recurrences among children with normal vascular imaging, children with a vascular abnormality had a 5-year cumulative recurrence rate of 66%. CONCLUSIONS. Strokes recur in one fifth of cases of later childhood arterial ischemic stroke but are rare after perinatal stroke. Among the later childhood cases, cerebrovascular imaging identifies those at highest risk for recurrence.

Preclinical atherosclerosis due to HIV infection: carotid intima-medial thickness measurements from the FRAM study

Background:Cardiovascular disease (CVD) is an increasing cause of morbidity and mortality in HIV-infected patients. However, it is controversial whether HIV infection contributes to accelerated atherosclerosis independent of traditional CVD risk factors. Methods:Cross-sectional study of HIV-infected participants and controls without pre-existing CVD from the study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM) and the Multi-Ethnic Study of Atherosclerosis (MESA). Preclinical atherosclerosis was assessed by carotid intima-medial thickness (cIMT) measurements in the internal/bulb and common regions in HIV-infected participants and controls after adjusting for traditional CVD risk factors. Results:For internal carotid, mean IMT was 1.17 ± 0.50 mm for HIV-infected participants and 1.06 ± 0.58 mm for controls (P < 0.0001). After multivariable adjustment for demographic characteristics, the mean difference of HIV-infected participants vs. controls was 0.188 mm [95% confidence interval (CI) 0.113–0.263, P < 0.0001]. Further adjustment for traditional CVD risk factors modestly attenuated the HIV association (0.148 mm, 95% CI 0.072–0.224, P = 0.0001). For the common carotid, HIV infection was independently associated with greater IMT (0.033 mm, 95% CI 0.010–0.056, P = 0.005). The association of HIV infection with IMT was similar to that of smoking, which was also associated with greater IMT (internal 0.173 mm, common 0.020 mm). Conclusion:Even after adjustment for traditional CVD risk factors, HIV infection was accompanied by more extensive atherosclerosis measured by IMT. The stronger association of HIV infection with IMT in the internal/bulb region compared with the common carotid may explain previous discrepancies in the literature. The association of HIV infection with IMT was similar to that of traditional CVD risk factors, such as smoking.

Self-Reported Experiences of Racial Discrimination and Black-White Differences in Preterm and Low-Birthweight Deliveries: The CARDIA Study

OBJECTIVES We examined the effects of self-reported experiences of racial discrimination on Black-White differences in preterm (less than 37 weeks gestation) and low-birthweight (less than 2500 g) deliveries. METHODS Using logistic regression models, we analyzed data on 352 births among women enrolled in the Coronary Artery Risk Development in Young Adults Study. RESULTS Among Black women, 50% of those with preterm deliveries and 61% of those with low-birthweight infants reported having experienced racial discrimination in at least 3 situations; among White women, the corresponding percentages were 5% and 0%. The unadjusted odds ratio for preterm delivery among Black versus White women was 2.54 (95% confidence interval [CI]=1.33, 4.85), but this value decreased to 1.88 (95% CI=0.85, 4.12) after adjustment for experiences of racial discrimination and to 1.11 (95% CI=0.51, 2.41) after additional adjustment for alcohol and tobacco use, depression, education, and income. The corresponding odds ratios for low birthweight were 4.24 (95% CI=1.31, 13.67), 2.11 (95% CI=0.75, 5.93), and 2.43 (95% CI=0.79, 7.42). CONCLUSIONS Self-reported experiences of racial discrimination were associated with preterm and low-birthweight deliveries, and such experiences may contribute to Black-White disparities in perinatal outcomes.